CVE-2026-59923
6.1 · MEDIUMOverview
CVE-2026-59923 is a medium-severity vulnerability affecting mistune_project mistune. It was published on July 8, 2026 and has a CVSS 3.1 base score of 6.1 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 6.1, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, HTMLRenderer.safe_url() does not block percent-encoded javascript URIs, allowing attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version 3.3.0.
Remediation
Check the references section for vendor advisories and patches from mistune_project. Update mistune to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| mistune_project | mistune | >= 0, < 3.3.0 | Affected |
Frequently Asked Questions
What is CVE-2026-59923?
CVE-2026-59923 is a medium-severity vulnerability affecting mistune_project mistune. It was published on July 8, 2026 and has a CVSS 3.1 base score of 6.1 (MEDIUM).
How severe is CVE-2026-59923?
This vulnerability has a CVSS 3.1 base score of 6.1, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-59923?
Check the references section for vendor advisories and patches from mistune_project. Update mistune to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-59923?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-59923 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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